I read the paper by Jhee et al.1 with interest. The authors conducted a prospective study to investigate the effect of coffee intake on the development of chronic kidney disease in the general population. Coffee consumption was categorized into five groups, and the primary outcome was incident chronic kidney disease defined as an estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m2. Adjusted hazard ratios (95% CIs) of coffee consumers with 1 cup/day and ≥2 cups/day against non-drinkers for chronic kidney disease development were 0.76 (0.63-0.92) and 0.80 (0.65-0.98), respectively.